Fuses and circuit breakersFuses and

Fuses and circuit breakers
Fuses and/or circuit breakers are usually included in the output of d.c. power supplies
and also to isolate defective loads from an a.c. power line. The main difference
between a fuse and a circuit breaker is that a fuse becomes a permanent open circuit
when it faces large fault currents, but a circuit breaker opens the circuit to be protected
but can be reset manually or automatically to restore the normal operation of the
system. The fuse is faster in action when the current through it is larger. The fuse
acts in a time range of 10 ms to 10 ms. Fuses or circuit breakers are always placed
in series with the line and sometimes used in conjunction with a surge protective
device (SPD) as shown in Figure 5.14.